Question

From the above statements we can conclude that

• A. the magnetic field is directed into the plane of page
• B. the magnetic field is directed out of the page
• C. the magnetic field is toward left in the plane of page
• D. the magnetic field is toward right in the plane of page

Answer 1

Answer: (B)

the magnetic field is directed out of the page

$I=\frac{ϵ}{R}=\frac{24}{12}=2A$

Magnetic force $=IlBsin\frac{\pi }{2}=2\times 5\times {10}^{-2}\times B=\frac{B}{10}$

$2k{x}_1=mg;2k=\frac{mg}{x_1}$ and

$2k(x_1+x_2)=mg+IlB$

$2k{x}_1+2k{x}_2=mg+IlB$

$\frac{mg}{x_1}{x}_2=IlB$

$10\times {10}^{-3}\times 10\times \frac{0.3}{0.5}=\frac{B}{10}\Rightarrow B=600\times {10}^{-3}=0.6T$